Check out https://medialyse-photography.de
Go to your koken plugins folder
cd /Your/path/to/koken/storage/plugins
Clone the repository
git clone https://github.com/NiTRoeSE/koken-plugin-back2top.git
Go to your koken-plugin-back2top plugin folder
cd /Your/path/to/koken/storage/plugins/koken-plugin-back2top
Update the repository
git pull origin master
It´s possible to add your own style for the 'back2top' button. If you wanna have a custom style that matches your site, just add your own css in setup menu.